Bucking oscillations are vehicle longitudinal oscillations caused by introduction of energy into the engine-drive train-body oscillation system, especially during acceleration of the vehicle. The engine torque is transferred to the drive train via a flywheel, which acts as a torsion spring and must initially be distorted under the influence of the engine torque. If this occurs from a rapid torque buildup, overshooting of the flywheel occurs because of the kinetic energy stored in the flywheel, which manifests itself in the aforementioned category of bucking oscillations.
Measures can be taken to avoid bucking oscillations via which the engine torque is influenced in phase-directed fashion so that the longitudinal oscillations of the vehicle are prevented. Ignition angle adjustment, interventions in the fuel injection or deliberate influencing of throttle valve movement are considered as such measures. In the latter the gas pedal movement is ordinarily converted in attenuated fashion to movement of the throttle valve so that the throttle valve is opened with lower speed or time-delayed relative to gas pedal movement. In this procedure the bucking oscillations are reduced, but at the same time the response of the vehicle significantly deteriorates.
The problem underlying the invention is to prevent bucking oscillations reliably without adversely affecting acceleration behavior and exhaust behavior.
This problem is solved according to the inventions with the features of claim 1.